Leon explains: The principles of celestial navigation in under 3 minutes
15 August 2024 · 2 min · 3K views
What this video covers
Leon Schulz explains celestial navigation sight reduction in a concise tutorial aimed at ocean sailors.0:13 A sextant measures the angle between a celestial body and the horizon; the navigator records that observed altitude and notes the exact time.0:20 An assumed position — accurate to within roughly 30 miles — is then looked up in the nautical almanac to find the altitude that should have been measured from that spot.0:46 The difference between the observed and tabulated altitude gives a distance from the assumed position, producing one line of position.1:15 A second line, from a second celestial object or a later sun sight, crosses the first to fix the boat's location.1:30 For a running sun fix, the morning sight's line of position is advanced along the course and distance traveled before crossing it with the noon or afternoon sight.2:27 Schulz notes that two objects work simultaneously — sun and moon in daytime, a planet and a star at twilight.0:47 Final accuracy is a handful of miles, and any initial position error corrects itself by the following day.0:46
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